A Liquid Crystal Display (LCD) is a display apparatus with an ultra-thin plane, consisting of a certain number of color or black and white pixels, and disposed in front of a light source or a reflective surface. The liquid crystal display enjoys its popularity and becomes a mainstream of the display due to its low power consumption, high-definition, small in size and light-weight etc. Most of the liquid crystal displays on the market are backlight type liquid crystal displays including a liquid crystal panel and a backlight module which are disposed to face each other, and the backlight module providing a light source to the liquid crystal panel for displaying so that the liquid crystal panel displays an image.
In recently years, as the High-Dynamic Range (HDR) technology is increasingly applied to digital photography, film art, television and other fields. To realize the HDR technology in the liquid crystal display, a special technology requirement is put forward for the liquid crystal display, that is, the liquid crystal display should be capable of realizing a control to partitions. The more partitions of the liquid crystal display have, the better the local dimming effect is, and the higher the dynamic contrast is, the better the picture quality is. The introduce of the local dimming technology on the liquid crystal display may usually need to partition the backlight of the liquid crystal display, a partition includes several light or one light, a main board analyzes brightness of each partition according a brightness algorithm of an image signal in real time, a backlight driving chip is controlled according to the analysis result to drive each partition in the backlight, thereby achieving the purpose of performing real-time brightness adjustment to the backlight, so that a bright region gets brighter, and a dark region gets darker, which can improve the dynamic contrast and realize energy saving.
The backlight module mainly includes a direct type backlight module and a edge type backlight module, the direct type backlight module may have a better local dimming effect since partitions of LEDs can be in one-to-one correspondence to partitions of liquid crystal glass, thus becomes mainstream of the market, especially to a large-sized liquid crystal panel, and as the backlight area is large, a pitch between LEDs is large, thus a backlight crosstalk between respective partitions is small, and the HDR effect is also good. As for a small-sized liquid crystal display, a pitch between LEDs in the backlight is small, thus it is impossible to implement effective multi-partitions, and a crosstalk of light between the partitions is large, thus the HDR effect thereof is poor.